For the benefit of those at the back of the class who have not been keeping up with London's latest literary sensation: Hanif Kureishi has just published a roman à clef about V.S.Naipaul and his wife Nadira, entitled The Last Word. Patrick French's notorious biography of the great writer provides Kureishi with the framework for his fiction, although he claims never to have read French. (Full disclosure: Sir Vidia is on the editorial advisory board of Standpoint.)

Needless to say, Kureishi's novel is brilliantly written and thoroughly enjoyable. But reading it is a guilty pleasure. Like the merciless French biography and the earlier hatchet job by Paul Theroux, Sir Vidia's Shadow, The Last Word is, to say the least, uncomplimentary about its main subjects. The reader sees everything through the eyes of the biographer, Harry, who is young, handsome and clever — seemingly the authorial voice. The Naipaul character, Mamoon Azam, is a foul-mouthed, lecherous, misogynistic egotist, who beats up his biographer when the latter reveals his past sexual depravities. Mamoon's wife, Liana, is a vain, hysterical, manipulative snob who exploits those she sees as her social inferiors. To this toxic cocktail, Kureishi adds a dash of politics: Mamoon is popular on the Right and has even been on terms of mutual admiration with Margaret Thatcher. A monster, in other words: irredeemable even by his unashamed elitism ("too cerebral, unyielding and harrowing to be widely read"), and increasingly pitiable as he declines into his dotage.

The Naipauls have taken their latest public lampooning "on the chin", as Sir Vidia likes to say. Despite having given Kureishi every assistance, including reading chapters at his request, Lady Naipaul bears no grudge over this latest onslaught: "That naughty Hanif has everyone in a tizzy," she wrote to me.

Yet I wonder whether the Mamoon of the novel is, as everyone has assumed, a portrait of Naipaul. The main reason for doubting this is that Mamoon is a Muslim from the Indian subcontinent, while Naipaul was of course born in Trinidad into a family of Hindu immigrants from India. In other words, Mamoon has more in common with Kureishi, himself the son of a Pakistani Muslim, than with Naipaul. There is a telling passage where Mamoon's ex-lover, Marion, describes her relationship with him in America: "‘Don't forget,' she said. ‘He was a Muslim man, and basically thought of women as servants. I advanced him, but there's only so far you can go.'" Mamoon does indeed treat all the women in the novel as servants — but in this crucial respect his personality could hardly be less like Naipaul's. Those who have known Naipaul ever since he came to Oxford in 1950 on a scholarship, and during his subsequent years as a writer in London, testify that he was always more comfortable with women than with men, kind and courteous to a fault. Kureishi's Muslim patriarch is not Naipaul.

What Kureishi and Naipaul do have in common is an unusual degree of introspection, along with an exalted sense of the writer's vocation. It may not be too much to say that Kureishi identifies strongly with Naipaul as the first post-imperial figure in English literature, and sees himself as occupying a comparably pioneering role for his generation of Asian immigrants. (Naipaul is 81, Kureishi 59.) Kureishi certainly seems impressed by the fact that Naipaul grasped the danger of radical Islam long before others in works such as Among the Believers and Beyond Belief, both written before 9/11.

Otherwise, they share neither convictions nor tastes. Mamoon is the writer Kureishi dreads becoming, but never the writer Naipaul actually is. Rather as Thomas Mann caricatured his older contemporary Gerhart Hauptmann as the mysterious Mynheer Peeperkorn in The Magic Mountain, so Kureishi has used the outlines of Naipaul's life to flesh out a myth that of the artist, for whom messy relationships or sexual aberrations are insignificant.

By the end Harry, the biographer, has convinced himself that his warts-and-all portrait has captured the essential Mamoon "without traducing him". The novel ends with a resounding peroration: "He had completed his work, which was to inform people that Mamoon had counted for something as an artist, that he'd been a writer, a maker of worlds, a teller of important truths, and that this was a way of changing things, of living well, and of creating freedom." Harry's Mamoon sounds much more like Kureishi — who told an interviewer that "all writing is a selfie" — than Naipaul. The latter really does tell us important, though unpalatable, truths: "The world is what it is; men who are nothing, who allow themselves to become nothing, have no place in it." The world is what it is not least thanks to V.S. Naipaul's monumental achievement. By sticking his selfie into the empty frame of a grand old man's portrait, naughty Hanif is still trying to define his own place in the world. The Last Word won't be his last word on that.